Paul raised less than $3 million in October and little more than $2 million in November when you factor out 11/5. He made an average of $6.6 million a month last quarter, and he's made $4 million this January. Not exactly a huge difference.
If Paul were even considering dropping out, he could set a fundraising goal to keep him in the race and I'm sure we'd meet it. If he's not worried about his House seat, I'm sure he'll stick around, especially if McCain delivers a double-knockout to Huckabee and Romney today. If everyone thinks McCain has won and is running effectively unopposed, they'll let their guard down and Paul can take advantage of that.